I have the stock front suspension in a 49 F1 truck, it pulls to the left, and wanders around pretty bad but never pulls to the right. the toe in is set between 1/16 and 1/8 tires look to be wearing ok with maybe a little scrub on the outside edge, tires are radial 235 15's steering box is from a 53-55 f100 and is adjusted snug but not binding in any way I can't find my shop manual to look this up so I'd appreciate a little help, I do have about 1/4" of play when I check for kingpin wear on the passengers wheel (thats about how much the wheel moves at its outermost edge) the drivers side is real good. can that little bit of play make it I am in the middle of swapping in a 56 f100 box but it appears that the column is at a different angle out of the box than the one in there so I'll be putting the old one back in rather than redrilling the mounting holes at the frame again
Its pulling to the left WHEN? while just driving ----or under braking?[or both]? how are the frt springs and shackle bushings?
Is the frame square for sure? You might triangulate the measurements and check it to see if it has been 'racked"in a previous life....
pulls left while driving and braking front springs are good and so are the shackle bushings, I put new ones in when I changed the springs, new shocks last year as well, it has disk brakes on the front, new wheel bearing this spring as well I didn't think of a bent frame, it sits level and don't appear to dogtrack a bent frame isn't something I want I do have the frame from the 48 if it comes to that, I guess I'll have something to do this spring
Many things can cause a vehicle to pull. It a process of elimination that will determine the cause. Start with does the pull happen ,or change when brakes are applied ?If so check the brakes most likely it will be a brake assy on the side of the pull. If the pull is constant check the tires for air pressure and wear .Be on the look out for any uneven wear patterns as these will be indicators of where the problem may exist. Be careful of the cheap parts store tires 4/ $125.00 . They seem to have an extremely high problem rate. To rule out tires simply swap the fronts left to right and vice a versa . Dont forget to remount back to their original side. If this changes the condition check tires further as there may be a defect in one . again it will be on the side of the pull. Still no luck. Check all suspension joints and bushings. for wear or movement. You have already stated that the pass king pin bushing has a 1/4" of play . This could be your most likely problem. When you move the tire have someone watch the movement at the king pin if its moving more that a 1/16" consider changing the bushing. Check tie rods Compress the tie rod ball joint with a large pair of pliers or a bar If the joint compresses more than 1/8" change the joint. Worn susp parts will cause the wander your describing . Whats the reason for the changing of the gearbox? If everthing is ok so far . Measure the distance from the c/l of the front rear spring eyelet bolt to the c/l of the lower frt spindle .Preferably should measure within 1/8" but not exceed 1/4" . If 1/4" or more check eyelet bushing and axle position on spring sometimes the beam will shift on the spring if the bolts are loose or the locating pin snaps. You mentioned new springs. Double check this area carefully . If you still have a problem your going to need alignment measurement data from the truck for further diagnosis. I believe the king pin bushing may be causing the pull especially if the r/f wheel is being allowed to move outward at the bottom. This would change the camber from a + to a -.(knockkneed) . Check with a good local suspension shop sometimes they'll do the identification for free or a small charge. Larry
Palosfv3 I was changing the steering box because I had lopped off the column and hooked up a gm one to it via a rag joint but I honestly don't see any play at the joint, I wouldn't even worry so much about the pulling to one side its the wandering around that is making it no longer any fun to drive, I'll go over the front end and recheck everything to make sure its still snug and nothing out of the ordinary, tie rods are in good shape with one being new and the other tight as the new one once I get it all back together I'll check that kingpin again with the tires on the ground A dumb question but can you spell this out abit simpler for me? I never heard of this before and don't know what c/l is ------------------ If everthing is ok so far . Measure the distance from the c/l of the front rear spring eyelet bolt to the c/l of the lower frt spindle .Preferably should measure within 1/8" but not exceed 1/4" ------------------------ I been asking around about an alignment shop but to be honest I have never had good luck going to them, it seems I have to fix more crap when they are done than was corrected with the alignment, ie holes in headers due to being used for leverage points, loose clamp nuts and this is from a "reputeable shop" thanks for the info so far!
Pretty sure C/L means Center Line. Are tire pressures equal on both sides? Equal backspacing and wheel size the same on both sides?
If you have radial tires switch them left to right on the front, if it goes right its tires. If you have radials and bias plys mixed it will feel wandery. Is your steering gear tightened up?
I used the c/l as an abbreviation for centerline. Your have to establish that the measurements for the suspension control points / wheel length position are consistent from side to side .All vehicles have places to pick up measurements. An example would be from the lower ball joint grease fitting to the edge of a hole in the chassis that has been verified to be in the same spot on both rails. If the measurement is shorter on one side than the other it will cause a pull to the short side. If this length is short it also causes changes to the caster for the wheel. If caster is less than 1/2 degree it can cause the wandering your describing. ( to explain caster think of a bicycle . If you look from the side at the fork you can see the angle of the fork in relationship to the wheel . this angle is called caster. its critical for proper tracking ) If the condition was present with the original gearbox there is a possiblilty that the sectorshaft could be worn. Hi mileage tends to wear a spot out in the middle of the shaft .Cars spend almost all miles going straight and your constantly makeing small corrections as you drive. All this wear is concentrated in a small area on the center of the sector shaft and the imput gear. There is an adjustment on some gearboxes to address this issue but once your at the point that you need to adjust ,it usually binds up at the outer limits of the steering shaft rotation.This leads to failure of the box. If you have to adjust the gearbox to reduce this play. Its just better to get a new one . your only delaying the inevitable. If you need any further help PM and I'll send my phone # .Its easier to explain than type. Larry
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